// compute the right amount of padding to ensure menu items fill the bar

var INITIAL_PADDING = 10;
var DESIRED_WIDTH = 950;

// sum an array
function sum(arr) {
	var t = 0;
	for (var i = 0; i < arr.length; i++) { t += arr[i]; }
	return t
}

function padMenu() {
	var menuitems = $$('#menu > li > a');
	var width = sum(menuitems.map(function (e) { return e.offsetWidth; }));

	var pad = parseInt((DESIRED_WIDTH - width) / (2 * menuitems.length) + INITIAL_PADDING);
	if (pad > 0) {
		menuitems.each(function (e) {
			e.setStyle({
				paddingLeft: pad + 'px',
				paddingRight: pad + 'px'
			});
		});
	}
}

Event.observe(document, 'dom:loaded', padMenu);